A sequence of digital images, such as, for example, a sequence of video frames of a talking person, may include images of a human face. In various computerized applications, it may be desirable to estimate features of the mouth, such as, for example, the location and shape of the lips in images of that sequence. Deformable mouth model templates may be used for that purpose.
A deformable mouth model template is a model approximating the location and shape of a mouth. For the deformable mouth model template to estimate the shape and location of the mouth for a given image of a human face, an energy objective function may be minimized.
The quality, accuracy and robustness of the estimation of mouth features may depend on the structure of the deformable mouth model template used, and/or on the energy objective function used, and/or on the minimization algorithm used.
It will be appreciated that for simplicity and clarity of illustration, elements shown in the figures have not necessarily been drawn to scale. For example, the dimensions of some of the elements may be exaggerated relative to other elements for clarity.